1. Technical Field
The present invention relates to a recording apparatus which performs recording on a medium.
2. Related Art
Hereinafter, an ink jet printer as an example of a recording apparatus will be described. The ink jet printer includes a recording head which discharges ink onto recording paper on a carriage. The carriage is guided by a guide member extending in a scanning direction (hereinafter, referred to as “main scanning direction”) of the recording head. Further, the carriage is fixed to a part of an endless belt, for example, and is configured to reciprocate in the main scanning direction being pulled by the endless belt.
Generally, a position on the carriage at which the endless belt is fixed and a gravity center position of the carriage cannot be equally matched. Therefore, when the endless belt pulls the carriage, a phenomenon that the carriage tries to rotate (also referred to as “wobbling phenomenon”) is generated and ink landing accuracy is lowered in some cases. The carriage wobbles in several wobbling directions. When a paper transportation direction on a recording surface of paper is assumed as a y direction, a direction (paper width direction) orthogonal to the y direction is an x direction, and a direction orthogonal to the recording surface is a z direction, there are cases of a wobbling on an x-z plane, a wobbling on an x-y plane, and the like.
In JP-A-2006-96028, a recording apparatus having the following configuration in order to prevent a carriage from wobbling has been described. That is, in the recording apparatus, a biasing unit which exerts a biasing force between a guide member (guide shaft) and the carriage is provided. Further, a rotation moment in a constant direction is given to the carriage in advance with the biasing unit so as to generate the rotation moment in the constant direction all the time regardless of a movement direction of the carriage, in order for the carriage to prevent from wobbling.
In addition, in JP-A-2004-17314, an image forming apparatus having the following configuration has been disclosed. That is, in the image forming apparatus, in order to suppress looseness between first and second guide members and a carriage, a slide contact surface which makes slide contact with each of the guide members is pressed against the guide members by a biasing member. Note that the first and second guide members are provided along the movement direction of the carriage.
There is an ink jet printer having a configuration in which a gap between a recording head and paper (hereinafter, referred to as “PG”) can be adjusted. With the ink jet printer, an appropriate recording result can be obtained regardless of the thickness of paper by adjusting the PG.
Various adjusting mechanisms of adjusting the PG have been proposed. For example, there is an adjusting mechanism which adjusts the PG by changing the height position of a guide member which guides a carriage in the main scanning direction.
As this PG adjusting mechanism, a case in which the PG is adjusted by providing a guide member in a fixed manner and changing a relative position between a sliding member which makes slide contact with the guide member on a carriage and a carriage main body is considered.
With this configuration, the guide member is not required to be displaced and cost of the apparatus can be reduced. However, if the PG is adjusted, the gravity center position of the carriage relative to the guide member and a carriage pulling position (position on the carriage at which an endless belt is fixed) relative to the guide member are changed. Accordingly, the magnitude of a rotation moment (degree of wobbling phenomenon) when the carriage is pulled is also changed with the PG adjustment. Therefore, it is desired to obtain an appropriate wobbling prevention effect regardless of the magnitude of the PG. However, in the above-described existing recording apparatuses, such technical problem has not been taken into consideration.